While the review of public order policing ordered by Metropolitan police commissioner Sir Paul Stephenson is welcome news, it takes us nowhere unless the review examines in detail the current containment policy operated by the Metropolitan police.

The use of "kettling", or the imposition of police cordons to contain crowds, was approved by the country's highest court not three months ago, but the tactic remains highly controversial. In Lois Austin v the Commissioner of Police of the Metropolis, the House of Lords was asked to consider the containment of 3,000 protesters in Oxford Circus on May Day 2001. Many of those detained without access to food, water or toilet facilities for more than seven hours were peaceful protesters, but the Lords argued that the presence of some potentially violent elements in the crowd justified the police's actions.

In reaching this conclusion, the court found that the "purpose" of the police's tactics should be taken into consideration when assessing whether the protracted detention breached the fundamental right to liberty. Lord Hope, giving the leading judgment, specifically cited "public safety" as a factor that should be balanced against the right to demonstrate and freedom of expression. But if "public safety" is the barometer, how can the tactics of the police be justified in the context of the tragic death of Ian Tomlinson and the alleged assaults on many of the other G20 protesters?

The court's endorsement means kettling is fast becoming common practice at a wide range of protests. While the media focused mainly on the violence outside the Bank of England, those at Bishopsgate climate camp, enjoying the peaceful workshops and vegan farmer's market, faced similar aggressive policing tactics. And there is disconcerting evidence that these tactics are being abused: in January thousands took to the streets in outrage at the widespread human rights abuses in Gaza. At regular intervals the police corralled large sections of the public, which appeared to only fuel the atmosphere of frustration and encourage confrontation. While the overwhelming majority of demonstrators were simply exercising their right to protest, the police pressured even the youngest in the contained crowd to provide personal details, without any lawful grounds to do so. Those who refused were threatened with arrest under the wide-ranging powers afforded to the police by anti-terror legislation.

These tactics can only deter peaceful protest and form obstacles to the lawful exercise of the right to demonstrate. Ms Austin is bringing her case to the European Court of Human Rights. We must rely on Strasbourg to take a more robust approach when protecting our right to peaceful demonstration, and hope that Stephenson's review overhauls police tactics to ensure our fundamental freedoms are protected.